x402
Verified
Open payment protocol for agentic and API-based machine-to-machine commerce.
Open protocol with no platform subscription by default; implementation costs and network fees depend on the stack used.
Pricing
Open source
Open protocol with no platform subscription by default; implementation costs and network fees depend on the stack used.
Who It's For
AI agent developersProtocol designersBlockchain developersAgent economy builders
Details
About x402
x402 is an open payment protocol built around the HTTP 402 status code that lets AI agents and APIs settle stablecoin micropayments per request. Created by Coinbase and stewarded since April 2026 by the Linux Foundation's x402 Foundation (participants include Cloudflare, Google, Stripe, and Visa), it processed 165M+ transactions by April 2026 and is core infrastructure for the agent economy.
Key Features
- HTTP 402 payment standard implementation
- Agent-to-agent micropayments
- Open protocol for agent commerce
- Supports multiple payment rails
- Developer SDK and documentation
Pros & Cons
Pros
+ Solves real problem of agent payments
+ Open standard — not locked to any platform
+ Growing ecosystem adoption
Cons
- Very early stage technology
- Requires crypto/blockchain knowledge
- Limited real-world adoption so far
Use Cases
Agent-to-agent paymentsMonetizing AI skills and dataBuilding agent marketplacesMicropayment infrastructure
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